Dynamic Analysis of a Predator-Prey Model with Holling-II Functional Response

A predator-prey model with linear capture term Holling-II functional response was studied by using differential equation theory. The existence and the stabilities of non-negative equilibrium points of the model were discussed. The results show that under certain limited conditions, these two groups can maintain a balanced position, which provides a theoretical reference for relevant departments to make decisions on ecological protection.

The Dynamical Behavior of a Certain Predator-Prey System with Holling Type II Functional Response

In this paper we analytically and numerically consider the dynamical behavior of a certain predator-prey system with Holling type II functional response, including local and global stability analysis, existence of limit cycles, transcritical and Hopf bifurcations. Mathematical theory derivation mainly focuses on the existence and stability of equilibrium point as well as threshold conditions for transcritical and Hopf bifurcation, which can in turn provide a theoretical support for numerical simulation. Numerical analysis indicates that theoretical derivation results are correct and feasible. In addition, it is successful to show that the dynamical behavior of this predator-prey system mainly depends on some critical parameters and mathematical relationships. All these results are expected to be meaningful in the study of the dynamic complexity of predatory ecosystem.

The Dynamical Behavior of a Predator-Prey System with Holling Type II Functional Response and Allee Effect

In this paper, we mainly considered the dynamical behavior of a predator-prey system with Holling type II functional response and Allee-like effect on predator, including stability analysis of equilibria and Hopf bifurcation. Firstly, we gave some sufficient conditions to guarantee the existence, the local and global stability of equilibria as well as non-existence of limit cycles. By using the cobweb model, some cases about the existence of interior equilibrium are also illustrated with numerical outcomes. These existence and stability conclusions of interior equilibrium are also suitable in corresponding homogeneous reaction-diffusion system subject to the Neumann boundary conditions. Secondly, we theoretically deduced that our system has saddle-node bifurcation, transcritical bifurcation and Hopf bifurcation under certain conditions. Finally, for the Hopf bifurcation, we choose d as the bifurcation parameter and presented some numerical simulations to verify feasibility and effectiveness of the theoretical derivation corresponding to the existence of yk, respectively. The Hopf bifurcations are supercritical and limit cycles generated by the critical points are stable.

Global Asymptotic Stability and Hopf Bifurcation in a Homogeneous Diffusive Predator-Prey System with Holling Type II Functional Response

In this paper, we considered a homogeneous reaction-diffusion predator-prey system with Holling type II functional response subject to Neumann boundary conditions. Some new sufficient conditions were analytically established to ensure that this system has globally asymptotically stable equilibria and Hopf bifurcation surrounding interior equilibrium. In the analysis of Hopf bifurcation, based on the phenomenon of Turing instability and well-done conditions, the system undergoes a Hopf bifurcation and an example incorporating with numerical simulations to support the existence of Hopf bifurcation is presented. We also derived a useful algorithm for determining direction of Hopf bifurcation and stability of bifurcating periodic solutions correspond to j ≠0 and j = 0, respectively. Finally, all these theoretical results are expected to be useful in the future study of dynamical complexity of ecological environment.

Uniform persistence of multispecies ecological competition predator-pray system with Holling Ⅲ type functional response

The main purpose of this paper is to study the persistence of the general multispecies competition predator-pray system with Holling Ⅲ type functional response. In this system, the competition among predator species and among prey species are simultaneously considered. By using the comparison theory and qualitative analysis, the sufficient conditions for uniform strong persistence are obtained.

Impulsive Predator-Prey Dynamic Systems with Beddington-DeAngelis Type Functional Response on the Unification of Discrete and Continuous Systems

In this study, the impulsive predator-prey dynamic systems on time scales calculus are studied. When the system has periodic solution is investigated, and three different conditions have been found, which are necessary for the periodic solution of the predator-prey dynamic systems with Beddington-DeAngelis type functional response. For this study the main tools are time scales calculus and coincidence degree theory. Also the findings are beneficial for continuous case, discrete case and the unification of both these cases. Additionally, unification of continuous and discrete case is a good example for the modeling of the life cycle of insects.

Effect of adjuvant tiotropium bromide therapy on the oxygenation function and inflammatory response in patients with COPD and type Ⅱ respiratory failure

Objective:To explore the effect of adjuvant tiotropium bromide therapy on the oxygenation function and inflammatory response in patients with COPD and type Ⅱ respiratory failure. Methods:a total of 58 patients with COPD and type II respiratory failure treated in our hospital between August 2012 and January 2016 were collected and divided into observation group (n=29) and control group (n=29) according to the single blind randomized control method. Control group of patients received clinical routine treatment, and observation group of patients received adjuvant tiotropium bromide treatment on the basis of routine treatment. Before treatment and 30d after treatment, spirometer was used to determine pulmonary ventilation function;blood gas analyzer was used to test oxygenation function indexes;enzyme-linked immunosorbent assay (ELISA) was used to detect serum inflammatory factor levels.Results: Before treatment, differences in pulmonary ventilation function, oxygenation function and serum inflammatory factor levels were not statistically significant between two groups of patients. 30 d after treatment, FEV1, FEF75%, PEF, PaO2/FiO2, DO2 and O2ER levels of observation group were significantly higher than those of control group while VO2 level was significantly lower than that of control group;serum IL-1β, IL-18, IL-27 and CRP levels were significantly lower than those of control group.Conclusion:Adjuvant tiotropium bromide treatment can optimize the pulmonary ventilation and oxygenation function and reduce systemic inflammatory response in patients with COPD and type II respiratory failure.

Predicting plant traits and functional types response to grazing in an alpine shrub meadow on the Qinghai-Tibet Plateau

The identification of easily measured plant functional types (PFTs) that consistently predict grazing response would be a major advance.The responses to grazing of individual traits and PFTs were analyzed along a grazing gradient in an alpine shrub meadow on the Qinghai-Tibet Plateau,China.Three response types were identified;grazing increaser (GI),grazing decreaser (GD),and neutral (NE) for both traits and PFTs.Seven traits were measured:plant height,economic group,cotyledon type,plant inclination,growth form,life cycle,and vegetative structure.The first five were significantly affected by grazing.Ordinal regressions for grazing response of the seven traits showed that the best single predictors of response were growth form (including the attributes "Scattered","Bunched" or "Closely Bunched"),and plant inclination ("Rosette","Prostrate",or "Erect"),followed by economic group ("Shrub","Grass","Sedge","Legume","Forb",or "Harmful") and plant height ("Tall","Medium",or "Small").Within the four optimal traits,the summed dominance ratio (SDR) of small plants,forbs,rosette and bunched plants,invariably increased,while that of tall plants,shrubs,grasses,and erect plants decreased,when grazing pressure was enhanced.Canonical correspondence analysis (CCA) identified eleven explanatory PFTs based on 195 defined PFTs,by combining the different attributes of the four optimal traits.Among explanatory PFTs,the most valuable in predicting the community response to grazing were Tall×Shrub×Erect×Scattered and Small×Forb×Rosette,as these have the closest connections with grazing disturbance and include fewer species.Species richness,diversity,and community evenness,did not differ among grazing treatments because turnover occurred in component species and their relative abundances along the grazing gradient.We have demonstrated that a minimum set of PFTs resulting from optimal individual traits can provide consistent prediction of community responses to grazing in this region.This approach provides a more accurate indicator of change within a changing environment than do univariate measures of species diversity.We hope to provide a link between management practices and vegetation structure,forming a basis for future,large scale,plant trait comparisons.

A Stage-Structured Predator-Prey System with Impulsive Effect and Holling Type-Ⅱ Functional Response

A stage-structured predator-prey system with impulsive effect and Holling type-II functional response is investigated. By the Floquet theory and small amplitude perturbation skills, it is proved that there exists a global stable pest-eradication periodic solution when the impulsive period is less than some critical values. Farther, the conditions for the permanence of system are established. Numerical simulations are carried out to illustrate the impulsive effect on the dynamics of the system.

Positive solutions for a Lotka-Volterra prey-predator model with cross-diffusion and Holling type-Ⅱ functional response

We consider a Lotka-Volterra prey-predator model with cross-diffusion and Holling type-II functional response.The main concern is the existence of positive solutions under the combined effect of cross-diffusion and Holling type-II functional response.Here,a positive solution corresponds to a coexistence state of the model.Firstly,we study the sufficient conditions to ensure the existence of positive solutions by using degree theory and analyze the coexistence region in parameter plane.In addition,we present the uniqueness of positive solutions in one dimension case.Secondly,we study the stability of the trivial and semi-trivial solutions by analyzing the principal eigenvalue of the corresponding linearized system,and then we characterize the stable/unstable regions of semi-trivial solutions in parameter plane.

Almost periodic dynamics of delayed prey-predator model with discontinuous harvesting policies and Hassell-Varley type functional response

In this study,a class of delayed prey-predator model with Hassell-Varley type functional response is investigated,in which the harvesting policies are modeled by discontinuous functions.Based on functional differential inclusions and set-valued analysis theories,the local and global existence of positive solution in sense of Filippov is given.By employing theory of functional differential inclusions and generalized differential inequalities,some sufficient conditions which guarantee the permanence of the system are obtained.Accord- ing to non-smooth analysis theory with generalized Lyapunov functional approach,a series of useful criteria on existence,uniqueness and global asymptotic stability of the almost positive periodic solution to the system are derived.Some suitable examples together with their numerical simulations are given to illustrate the effectiveness of our results by using MATLAB.

MULTIPLE POSITIVE PERIODIC SOLUTIONS IN A IMPULSIVE PREDATOR-PREY SYSTEM WITH TYPEⅣFUNCTIONAL RESPONSES

The main purpose of this paper is to explore the existence of positive periodic solutions to impulsive predator-prey systems with type IV functional responses. Sufficient criteria are obtained for the existence of strictly positive periodic solutions. The approach is based on a continuation theorem in the coincidence degree theory as well as some prior estimates. This is also the first time that multiple positive periodic solutions are obtained using coincidence degree theory in impulsive ecological systems.

ALMOST PERIODIC SOLUTION OF MULTISPECIES COMPETITION-PREDATOR SYSTEM WITH ROLLING'S TYPE Ⅲ FUNCTIONAL RESPONSE

In this paper, we consider a nonautonomous multispecies competition-predator system with Holling＇s type Ⅲ functional response. The coexistence of the system, under some conditions, is obtained. Furthermore, using Lyapunov function, we show that the system has a strictly positive almost periodic solution which is globally asymptotically stable.

一种新型液压导管应变测量装置设计与研究

针对飞行器液压导管应变测量环境复杂,传统有线测量设备传感器布置困难、引线多等问题,提出了一种新型液压导管应变测量方法。该方法基于频响函数法建立测量装置与导管的动力学模型,研究了两者之间的应变映射关系,设计了可拆卸式测量装置,实现传感器非接触测量导管应变;结合理论计算和有限元仿真,研究了测量装置对导管模态及应变的影响,优化了装置设计及相关尺寸参数;通过试验验证有限元仿真结果,检验了装置非接触测量液压导管应变方法的有效性。结果表明,测量装置对导管应变影响微弱,300 Hz以下应变重构相对平均偏差为6.2%,证明测量装置能够有效测得导管应变,该方法和装置有望解决复杂测量环境下飞行器液压导管应变的快速准确测量问题。

甘精胰岛素U300联合口服降糖药治疗2型糖尿病的临床效果观察

目的探讨甘精胰岛素U300联合口服降糖药治疗2型糖尿病的临床效果。方法选择2021年10月—2023年1月广东省吴川市人民医院收治的79例2型糖尿病患者,随机分为非甘精组(39例)和U300组(40例)。非甘精组口服降糖药物治疗,在此之上,U300组增加甘精胰岛素U300治疗,持续治疗3个月,对比2组血糖及相关指标变化,并监测患者胰岛素功能相关指标改善情况,评估低血糖反应等不良反应情况。结果治疗后,U300组血糖指标、血糖波动指标均显著低于非甘精组,差异有统计学意义(P<0.05)。U300组治疗后胰岛素功能指标均显著优于非甘精组,空腹及餐后2 h C肽均显著高于非甘精组,差异有统计学意义(P<0.05)。U300组低血糖反应发生率(2.50%,1/40)和不良反应总发生率(20.00%,8/40)与非甘精组(2.56,1/39;17.95%,7/39)比较,差异无统计学意义(P>0.05)。结论增加甘精胰岛素U300治疗,可更好地提升患者血糖管理效果,并可改善胰岛功能,有利于稳定控制血糖,有助于提高患者病情控制效果,应用效果安全可靠。

一类具有修正Leslie-Gower和Holling-type Ⅲ型的时滞食饵捕食模型的周期解与持久性（英文）

本文研究了一类具有修正的Leslie-Gower和Holling-typeⅢ型时滞食饵捕食模型.运用重合度理论和比较定理,得到系统正周期解和持久性的充分条件.结论拓展和完善了已有的结论.最后,从例子可以看到结论是容易验证的.

响应型润滑表面的智能调控研究进展

智能润滑材料和表面具有随需应变和仿生功能的特点,是近年来润滑技术的一个研究重点。功能成分的触发和反馈行为赋予了智能材料可控的润滑能力,能对环境变化做出响应,进而可以实现摩擦界面润滑状态的主动调控,为智能设备的设计和运用提供新的研究思路。结合智能润滑的研究现状,对材料类型、构筑方式以及应用领域等研究进展进行介绍。根据材料能够响应的刺激类型把智能润滑表面分为9种类型,并分别总结了每种类型材料的设计理念、刺激响应机理以及性能特点。此外,从高分子复合材料、功能化润滑纳米添加剂和环境敏感水凝胶3个方面对智能润滑表面的摩擦学领域的应用情况以及未来可能发展的方向进行了讨论。未来研究方向包括但不限于以下几个方面:一是开发新型响应型润滑表面,例如基于自愈性润滑表面、电磁响应性润滑表面等;二是探索更加智能的响应机制,例如基于人工智能的自适应控制;三是进一步研究响应型润滑表面的机理,从微观和宏观层面深入探索响应机制;四是拓展响应型润滑表面的应用领域,例如在纳米技术、生物医学、机器人等领域的应用。

具有Leslie-Gower和Holling-III型功能反应的捕食-食饵模型的一致持续生存

研究了一类具有Leslie-Gower和Holling-III型功能反应的捕食-食饵模型,利用微分不等式和一些分析技巧获得了关于该模型一致持续生存以及存在周期正解的充分条件.

从行为人刑法到行为人类型——责任理论的建构

人格刑法理论在出罪层面可以成立,但存在犯罪论体系不成熟、人格测量不精确、商谈性缺乏的短板,未能落实到司法实践。应当依托阶层体系与功能责任论,在责任要素下建构商谈性的行为人类型教义,以综合行为刑法的安定性与行为人刑法的预防性,联结个案事实与人格概念、日常语言与法律语言。从人格概念出发,罪责是不法行为与犯罪人格之间显现与被显现的对应关系,需罚性是显现的人格有处罚必要。在“藏区一妻多夫”“帮派一般参与者”等类型中,责任要素不成立,即行为不能归属于犯罪人格,或显现的人格没有处罚必要,刑事责任不成立。